Porous rubber fabric and method of producing the same.



APPLICATION FILED JULY`20. i916.

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vPatented June l2, 1917.

| ds--- A a EL m. if .T 2 V 2 N /mU. Z 0. Y L B M 2 un 2 ATTORNEY' .t TEUR B. HEEL, OF Isola l N, OHIO, ASSIGNOB TD THE B. F. GOODBICE COW, OF

NEW YORK, N. Y., f CORPORATION 0F NEW YORK.

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The object of this invention is to provide a flexible sheet of water-proof material traversed by a relatively large number of line holes..

0f the accompanying drawings,

Figure 1 is a magnified view of a waterproof woven fabric embodying my invention,

v with a portion of the proofing ,material removed from one side. l

Fig. 2 is a perspective view showing the process of coating the fabri`c"andublow1ng holes through the coating.

Fig. 3 is a cross-section of the compressedair nozzle.

The preferred mode of carrying out my invention consists, in brief, in .providing a l woven textile fabric with one or more coats of rubber in an ordinary yspreading machine, blowing holes through the rubber coating before it has com letely dried, and finally vulcanizing the ru berized porous fabric.

For example, in Fig. 2, 10 is a stock-roll from which the uncoated cotton Aor other woven textile fabric 11 is unwound, and 12 is a batch of vulcanizable rubber cement placed on the fabric in the cleft between a scraper or spreader blade-13 and a roller 14, and confined at its ends by the side plates 15. h6, 16 are two of the series of steam-heated drying plates over which the coated fabric passes 1n order that the solvent may be driven o' from the cement by evaporation,

17 is the fabric guide-roller at the rear endil and 18 is the take-up roller for the coate fabric, these parts forming the essentials ofV anordinary rubber spreading machine.

Arranged transversely underneath the coated fabric, between the spreading blade 13 and the first of the drying plates 16, is

a nozzle pipe 19 attached to a compressed-air supply pipe 20 and having a narrow slot 21 in its upper wall, by means of which compressed air or other suitable Huid under pressure, may be blown through the fabric, and the partially-dried rubber coating thereon, with the eect ofbreaking the coating in Specification of Letters Patent.

Application um .muy ao, 191e. sum1 no. 110.3135.

numerous places at the points of least resistance to the passage of air, namely, over the interstices 22 (Fig. 1) betweenthe threads 23 of the fabric. In this operation, none, or substantially none, of the rubber is removed. 24 is the rubber coating shown on the lefthand part of Fig. v1, and 25, 2o represent conventionally the holes in the coating.

rlhe rubber partly impregnates the textile fabric and it is ordinarily desirable to coat the same on both sides, the fabric being turned over and repassed through the spreading machine for that purpose and preferably being given more than one coating on the side which is exposed to a liquid when in use and subjected to more or less wear. Each successive coat, after being spread, is blown through with air, in the manner described in connection with Fig. 2, to break the rubber films over the'interstices of the fabric. It is found that the exposed portions of each thread in the fabric becomepractically surrounded with rubber, so that the capillary action of the yarn, which is manifest in uncoated textile fabric, is largely overcome. Furthermore the rubber .coating embeds or locks up the projecting ne 'filaments or fuzz upon the yarn. Finally, the

product useful in various situations, andv particularly as the upper member or sheet of a diaphragm adapted to be used in concentrating metallic ores by the oil-dotation process, which requires thebubbling of compressed air in very fine streams through the ott'om of a tank in which the liquid and suspended solid matter are held during treatment. The diaphragms heretofore in use in4 such apparatus have proved unsatisfactory and short-lived, and my invention provement in that v connection. It is desirable in an ore-{iotation diaphra that the holes shall be very small relat1vely to.

the intervening impervious portions of the diaphragm. A sheet of woven fabric, embodying my invention and suitable for the vhas been found to afford `a substantial impurpose mentioned, shows` its porous character when held to the light, although it is ing.

not essential that every one of the interstices should be open, and some of the holes are/ porous2 so small as to be invisible to the naked eye.

I claim:

1. A textile fabric open or porous at the interstices between the threads, and gumcoated on the rest of its surface.

2. A fabric of interwoven fibrous threads,

surfaced with rubber and porous at the inl terstices between the threads.

8. A closely-woven textile fabric continuously surfaced with vulcanized rubber which substantially incases the exposed portions of the individual threads, the rubber coating having` ne holes through it at the interstices between the threads.

4. The process of making water-proof,7

porous fabric which consists in, spreading rubber cement on the fabric, forcing a Huid under pressure through the fabric and thecoating toy perforate the latter, then evaporating the solvent and vulcanizing the coat- 5. The process of making water-proof, textile 'fabric which consists in spreading the fabric with successive coats of rubber cement, perforating the coats successively over the interstices between the threads by blowing compressed air therethrough, and vulcanizing the rubberized fabric. y v

6. The process of making water-proof, porous, textile fabric'which consists in coat- 111g and partially impregnating the threads of the fabric with rubber cement to an eX- tent sufiicient substantially to embed the projecting bers and overcome the capil-` larity of the threads, perforating thecoating at the interstices by iuid pressure, evaporating the solvent in the cement, and vulcanizing the rubber. In testimony whereof I have hereunto set my hand this twelfth day of July, 1916.

- ARTHUR B. KEMPEL, 

